When forming sheet metal products, one or more parts are formed in a piece of sheet metal and are connected to the sheet metal through one or more micro-joints. In order to separate these parts, it is conventional that subsequent mechanical or manual hammering or vibrating must be carried out with respect to the sheet metal. In addition to potential damage such as cuts, bends, and depressions formed on the part, the conventional parts separation process is noisy and labor intensive, increasing the overall costs of fabricating sheet metal parts.
U.S. Pat. No. 5,284,043 to Hayashi describes a process for separating a part from a sheet of metal. In order to separate the part from the sheet while avoiding damage to the part, the sheet metal and the part contained therein must be specially prepared. In particular, the part must be first contoured while leaving a small joint such as a connecting web or micro-joint which connects the part to the sheet metal, and thereafter, a protrusion must be formed on or adjacent to the joint by lancing, embossing, or semi-shearing, the sheet metal then being transported to the pressing operation to press the protrusion in order to shear the micro-joint. The necessity of specially preparing the sheet metal and the part contained therein requires specially designed machinery to perform that task. This increases the overall production cost of each formed part. The parts separation process described in the background of the Hayashi patent is typical of that utilized in the sheet metal industry.
Other industries have utilized different techniques for separating a component joined to a carrier sheet. For example, U.S. Pat. No. 4,467,948 to Deslauriers discloses a machine for stripping waste from previously die-cut blanks; U.S. Pat. Nos. 4,033,240 and 4,467,940 to Deslauriers disclose a device for automatically removing waste material from die-cut blanks; U.S. Pat. No. 3,391,589 to Bishop also discloses an apparatus for cutting blanks from board and separating the scrap from the blanks; U.S. Pat. No. 4,561,334 to Sarka discloses a rotary cutting device that cut blanks from thin sheets of webs of material such as paper, paper board, cardboard, plastic film, metal foil, sheet metal and the like; and U.S. Pat. No. 4,109,842 to Acquilla discloses a device for automatically stripping waste material from sheeting such as precut cardboard, the device incorporating projections which interact with the waste portion of the sheeting enabling its removal.
Other than the Hayashi patent, the other prior art references noted above all deal with separating products from a sheet carrier, the carrier comprising material other than sheet metal.
Due to the nature of the sheet metal working process, separating devices which can be utilized in other industries, such as cartons, paper, etc., cannot be efficiently and effectively utilized. As noted in the Hayashi patent, the separation process is typically carried out by manual means, i.e. after the microjoints are formed, sheets are typically delivered to an area where workers either shake the sheet to cause the micro-joints to sever or use hammers or other mechanical components to do the separation.
The lack of an automatic apparatus for use in the sheet metal processing industry to separate parts from the carrier (scrap) material and the requirement to use manual labor to do so adds greatly to the cost of the overall sheet metal process.
What is thus desired is to provide an automatic process for separating parts micro-joined to the metal carrier material which can be easily incorporated in the conventional processing line and which reduces the cost associated with the separation process now utilized in the sheet metal industry.